Evaluation of atrioventricular junction velocity by orthogonal polynomial fitting from cine magnetic resonance imaging and comparison with tissue Doppler Echocardiography

This study was carried out to (i) provide the methodology for determining atrio-ventricular junction (AVJ) motion from cine magnetic resonance imaging (MRI), and (ii) compare its derived velocities (i.e., myocardial systolic velocity Sm1 and early diastolic velocity Em) with tissue Doppler echocardiography in normal healthy subjects. Both cine MRI and Echocardiography were performed in 23 normal healthy subjects (age range: 19 to 70 years). From cine MRI, the AVJ were traced during cardiac cycle and AVJ displacement and velocities (i.e., Sm1 and Em) were derived using our in-house orthogonal polynomial fitting algorithm at both septal and lateral levels. From tissue Doppler echocardiography, Sm1 and Em were measured. Measurements of Sm1 and Em from cine MRI were 100% achievable within 5 minutes. Linear regression analysis found that there were significant correlations of Sm1 (r=0.68, P<;0.001) and Em (r=0.62, P<;0.001), respectively, between cine MRI and tissue Doppler echocardiography approaches. Furthermore, Sm1 from MRI was not correlated with age, while diastolic velocity Em from MRI was significantly correlated with age (r=0.53, P<;0.001). In conclusion, our method to quantify AVJ velocities hold potential to be adjunct to MR images in routine clinical practice.